#testingtuesday flux dosing and labelling


In previous #testingtuesday videos, we have shown borate fusion with our semi-automatic high frequency induction device Bead One HF. For automatic borate fusion, HERZOGs HAG-HF also features automatic high precision dosing of sample material and flux as well as automatic ultrasonic cleaning of platinum crucibles and dishes. Furthermore, HERZOGs automatic preparation machines like crushers and mills as well as XRF devices from various manufactures can be attached for a complete automation of sample preparation.

#testingtuesday disassembly tool


Disassembly Tool

This week @ our TestingTuesday Lab we would like to introduce our disassembly tool.
As you can see in this video, this tool will simplify the cleaning process of the press tools in the HP-MP by helping to remove the different components of the press tool.  With ease you will be able to remove the screws, the discs and the spring from the die and the piston.

#testingtuesday Borate Fusion

Bead One R

Part 2: Borate Fusion

Sample preparation is the second most important step for correct analysis results, only surpassed by sampling itself. Reproducible sample preparation is mandatory for excellent analytical results by e.g. xrf spectrometers. The Bead One R muffle furnace operates with highly accurate PtRh-Pt thermocouples for optimum fusion control. Crucible and dish are simultaneously inserted into the pre-heated oven chamber. After melting the flux, dissolving the sample and homogenizing the melt for a couple of minutes, the mixture is cast into the platinum dish within the oven thus ensuring temperature equality of melt and dish. Afterwards, crucible and dish are moved out of the oven and the dish is cooled passively as well as actively to create a perfectly homogeneous glass disc with no crystallization.

#testingtuesday Acid Digestion

Bead One R

Part 1: Acid Digestion

To be analyzed by ICP, samples have to be dissolved into a liquid. The fusion process is similar to the regular fused bead method but instead of casting the melt into a platinum dish, it is cast into an acid solution. The method allows complete digestion of materials like ferroalloys, sulfides or refractory materials. It increases operator safety as handling of dangerous acids like HF is avoided. Instead, less dangerous and diluted acids like HCl or HNO3 are used to dissolve the material after fusion with the flux.

#testingtuesday Temperature Calibration

Bead One HF

Part 4: Temperature calibration of Pt-Au crucibles

The emissivity of crucibles, especially commonly used Platinum-Gold crucibles, changes over time. As it is not possible to directly measure the emissivity, our calibration unit indirectly determines it by comparing pyrometer and thermocouple temperature within a lithium tetraborate melt. The fully guided semi-automatic calibration in the Bead One HF results in temperature stability of up to ± 5 °C. Therefore, temperature control in high frequency induction furnaces can be as good as in common resistance furnaces.

#testingtuesday HTP 40

HTP 40

After using the HSM 100 mill in the previous video, we can now use the sample for pressing in the HTP 40. The pulverized material is carefully being loaded into the steel ring. Please note that the equipment should be cleaned off any excess powder as you can see in the added picture. After closing the HTP 40 with the swing-out cross-head, a number of pressing variables can be selected, depending on the material prepared and the press tool employed. The pelletizing process of the press is controlled by the PLC program. Pelletizing parameters such as total pressing force, ramp up and decrease of pressure as well as pressure holding time can be preset on the HMI panel. This results in the production of a perfect pellet even with complicated sample materials.

#testingtuesday HSM 100

HSM 100

For manual or semi-automatic sample preparation, the HSM-100 disc mill can operate with different types and sizes of grinding vessels to enable preparation of all kinds of material. After loading the machine with pre-crushed material, grinding aid pills are added in order to reduce agglomeration rate and increase stability of the pressed pellet. Please note that usually only 4 to 8 pills are used to obtain a stable pellet. After loading the mill with the grinding vessel, a pre-defined program can be started by quickstart buttons. The ground material often has a maximum grain size less than 45 µm to reduce interference with XRF spectrometers. After using the HSM-100 mill, the sample is ready for pressing in e.g. an HTP-40 semi-automatic press.


HP-MP: Next Generation

Powder Preparation - Quick and repearable pressed pellets in the new HP-MP

Powder Preparation - Quick and repearable pressed pellets in the new HP-MP

For quick and repeatable sample preparation of powdered materials, the new HP-MP is perfectly suited. The mill- and press combination automatically pre-doses the material, grinds and presses it. Within only a very few minutes, the pressed pellet is ready for e.g. XRF analysis.


#testingtuesday Protection Wall

Bead One HF

Part 3: Automatic protection wall

In order to fuse so called platinum poisons, the preparation of the crucible with a protection wall is essential. Platinum poisons might cause devastating damage to platinum ware which can be avoided by the right preparation routine. The protection layer is formed with Lithiumtetraborate and covers the interior walls of the crucible, thus enabling pre-oxidation of materials that would otherwise react with the platinum. Furthermore, the automatic formation of a protection wall eliminates risks to the operator as no hot pieces have to be handled.

#testingtuesday Casting

Bead One HF

Part 2: Controlled Casting

After dissolving the sample material in the flux, the homogeneous liquid must be poured into a dish. The automatic casting mechanism of the Bead One HF ensures the emptying of the crucible in a controlled manner. The casting duration can be adjusted allowing even the last drop to be cast into the dish.

#testingtuesday Borate fusion

Bead One HF

Part 1: Borate Fusion

In the first stage of fusion, the flux melts and the cement sample is being dissolved. The high temperatures liberate carbon dioxide from the cement, which might form bubbles during the dissolution process. During the mixing step the melt is homogenized. This prevents formation of saturation layers around solids, thus the dissolution rate is kept high.